Maple Syrup is a Gift, by El Jeffe

Maple syrup is a gift of nature. Like all good gifts, it must be received. That happens in late winter and early spring in the New England and the Great Lakes regions. Since autumn, temperatures below 45 degrees have caused the trees to store sugar as starch. Around the end of February and into March, the sun begins to warm the maple trees even while the nights remain quite cold– below freezing. This fluctuation in temperature begins a pumping action in the sugar maple trees, which I interrupt by gathering sap.

The Tree Sugar Maple (also known as Rock Maple or Hard Maple) trees are the most common source of sugary sap. I am told that Black Maples are also especially good for tapping. Usually, Red Maples and Silver Maples should be avoided, if their sap is not as sugary, which consequently takes longer to evaporate. If my red and silver maples test below 1.5% sugar, I will avoid them. Their taste is also not as light and sweet. The Sugar Maple leaf is distinctive by its five-fingered leaf with deep “U” shapes between the fingers. The traditional Canadian Maple leaf symbol is quite similar to the sugar maple leaf. The leaves of Red and Silver Maples have distinctive jagged edges and “V” cuts between fingers.

I find that determining the type of maple tree by its bark can be as much art as science. In some trees, the Sugar Maple bark looks like elephant skin. It can be difficult to discern one variety from another. Another cue to discover your Sugar Maples is that their branches tend to branch off lower to the ground (six feet or so) when mature. An important consideration of a great producer is its crown the collection of branches at the very top of the tree. A great crown will draw a great amount of sap up from the roots and truck. Leaving nothing to chance, I mark my Sugar Maples in the autumn, before the leaves fall, with a small dot of spray paint.

The University of Maine has excellent resources on selecting trees, harvesting sap, and making maple syrup at:

Tap Using a 7/16″ bit, I drill a two-inch hole at a slightly uphill angle into the maple tree about three to four feet above the ground. I usually see sap immediately begin to wet the opening. Clean the tapped hole of any sawdust or debris. Using a rubber mallet, gently tap a 7/16″ plastic spile into the tree. The spile should be firmly seated in the white wood but not split the tree. Tap on warm days to avoid splitting the tree.

Connect the spile using a food grade plastic hose inserted into a 5-6 gallon pail which sits on the ground at the base of the tree. Some older stainless steel spiles permit hanging the bucket from the spile. That doesn’t work with the modern plastic variety, so I just put the collection buckets on the ground with a piece of wood on the cover to keep everything stable. The bucket requires a lid to prevent rain and snow from ruining the sap. On the side of the rim of the bucket, near the top, drill a hole for the plastic hose to go into the side of the bucket. My first year, I drilled a hole through the top of the cover, which was not a good idea since rainwater and melting snow contaminate your sap. Your collection operation is complete! It is that easy.

Responsibly tapping maple trees for sap does not damage the trees. The proof of that are the generations of “sugarbush” harvesters that tap their Maples every year. It is important to rest a tree every three or four years, arborists say. It is also important to tap only trees that are mature. The Michigan and Maine state websites about harvesting maple syrup agree that only trees with trunks more than 10″ in diameter should be tapped. If a tree is 10-20 inches in diameter, it has a circumference of 31″ to 61″ and can support one tap. A tree 20″-25″ has a circumference of 64″- 79″ and can support two taps. Over 25″ diameter trees can support three taps. A tree should not be tapped with more than three taps under any circumstances. Over-tapping a tree can starve it of the needed sap for its survival. Excess openings (taps) in the tree can also allow pests and infections to enter the tree.

The sap-rising temperatures– 40 degrees or so– will create pressure inside the tree and cause the sap to flow. Day and night, the running sap will drain into your collection bucket. During periods of great temperature fluctuations, I have harvested five gallons a day from a productive tap.

A sweet sap will be about 2% sugar and is measured in the field using a hydrometer. You will need to buy a long or short hydrometer ($10-$20) and a stainless steel cup ($18-$22) to hold the sap while testing. I buy all of my supplies from Sugar Bush Supply company I have found them them to be 100% reliable, fairly-priced, and knowledgable. Sap that is less than 2% is still usable, but it will take longer to evaporate and can result in a darker, more molasses-like syrup. The Grade A Amber syrup comes from the sweetest sap.


As soon as possible, boil your sap. If it stands for more than two or three days, especially in warm weather, it can become milky and affect the taste of the syrup. For my sap, I use a 125 gallon, food grade, polystyrene holding tank that I purchased from Leader Evaporators . Making maple syrup is about evaporating the water out of the sap. Roughly speaking (depending on the sweetness of the sap) 43 gallons of sap yields one gallon of syrup.

The sap is boiled to 7.5 degrees above the boiling point of water. At sea level this temperature is about 212 degrees Fahrenheit. So, since I am near sea level, I bring my sap to 219.5 degrees, when it becomes a clear amber yellow. Boiling above those temperatures will often result in gritty bits of “sugar sand” in the syrup and a cloudy product. Also, the longer the sap is boiled, the darker it gets. Inferior sap will yield a syrup that is “Class C”, brown, and molasses-tasting. The highest prized syrup is the golden, clear, light syrup.

In the past when doing small batches, I used an electric stove to boil my sap in stainless steel pots from Walmart. The evaporation/boiling process took about seven hours to turn 18-20 gallons of sap into two quarts of syrup. Because I will have several hundred gallons of sap this year, I decided to boil most of it on an outdoor steel box wood stove in the woodshed. I will use the stove top for the finishing process of taking the thickened sap to 219.5 degrees Fahrenheit.

Filtering and Bottling

Syrup should be filtered when it’s hot. I use homemade filters, but they can also be purchased at Sugar Bush Supply and other supply companies. The syrup should be bottled at a temperature of at least 180 degrees Fahrenheit to prevent bacteria and fungi. It is capped immediately and left to cool. I use 12 oz and 8 oz glass bottles, but there is a wide variety of containers, caps, and labels. Just make sure your jars and bottles are sterile before filling them. Bottles should be filled to near the top, minimizing the amount of air in the bottle. The bottle or jar can then be laid sideways to cool, creating a nice seal with the cap.

Reverse Osmosis

I have been reading and thinking about using a reverse osmosis (RO) machine to extract much of the water from the sap before I boil it. Most of the literature claims that the reverse osmosis filtering systems can extract up to 60% of the water out of the sap. Obviously, this would reduce the boiling time significantly.

However, I am concerned that the sugar in the raw sap would foul the filters frequently. If I have to replace filters every hundred gallons of raw sap, for example, that would require a lot of work and maintenance. For me this is a hobby, not a job. I am not convinced yet that using the RO filters makes sense for my small operation.

Clean Up

After the season is over, clean all of your hoses, spiles, and buckets with a hot chlorine-water solution. Use one part chlorine to twenty parts hot water. Then store your requipment in a dry, clean place. Cleanliness is critical in the process. Whenever I handle the raw sap, I usually filter it to remove any visible debris. Then, boiling it kills any unseen germs, bacteria, and contaminants.

Final Product

You are finished! Your maple syrup is delicious, pure and 100% natural, with no additives of any kind. I am told that maple syrup, like honey, will last for many years when sealed and stored in a cool, dark place.

Combined with your labor and a few materials, your maple syrup is a gift of nature.